Protests have spread in central Athens, amid anger over austerity measures being debated by parliament.

Protesters threw stones and petrol bombs, and police fired tear gas. A number of people were injured and at least 10 buildings were set on fire.

PM Lucas Papademos urged calm, saying violence had no place in a democracy.

MPs are voting on a bill to introduce the measures, which are being demanded in return for a 130bn-euro ($170bn; £110bn) bailout to avoid default.

The BBC's Mark Lowen in Athens says the violence is the worst the city has seen for many months.

Protesters hurled flares and chunks of marble torn up from the square. Some tried to break through a cordon of riot police around the parliament.

Several historic buildings, including cafes and cinemas, were in flames.

Syntagma Square - in the heart of Athens - is cloaked in a hail of tear gas, our correspondent adds.

The protests will come during a delicate phase of negotiations around the eurozone as the leadership in core countries like Germany and France express their desire to keep Greece in the euro while showing little room for compromise on the current conditions of the Greek bailout, which forces serious, arguably impossible-to-abide austerity measures on the recession-stricken economy.